Communications system for transmitting navigational information for road vehicles

A communications system for bidirectional, information transmission between vehicles of which each has a transmission/reception unit, a synchronisation unit, which assigns a transmission channel to a receiving transmitter, and a processor, which outputs the status of a vehicle to the transmission/reception unit or evaluates information received from the reception unit. Each vehicle has a global positioning system (GPS) module which repeatedly transmits its actual position. The synchronisation unit specifically assigns a separate channel for monitoring the pattern of movements of the associated vehicles, to each of a number of transmitters. A transmission channel is provided for communicating information specifically between a vehicle and a fixed-point transmit-receive unit, with the fixed transmission unit specifically communicating position-related information to the vehicle.